Say Your In Dino mode and You See A dinosaur Eating A Fresh Dinosaur You Could Roar At it And it Could Go like This:
1)It Roars Back Trying To warn You Off
2)It Runs away
3)It Fights
4)It lets You Eat Aswell

Ok, do you choose what dinosaur you get to be?

Do you get to hunt? And when you start as an egg are you in a nest with others or by yourself.

Others And yes You do Get To Hunt

Do you choose your Dino.
In Singleplayer Yes But In Multiplayer There are Limited Choices